Lasers utilize, for their operation, an active material located within a laser cavity which is made optically resonant by placing reflectors at either end thereof to form the optical resonator of the laser. One of the reflectors functions as an output coupler or means for transmitting laser light out of the laser cavity. Resonator reflector design is often specified to be within 1/10 or 1/20 of a wavelength of light and frequency to be within 1/100 of a wavelength of light. In other words, deviations in excess of 1/1,000,000 of an inch may not be acceptable.
It has long been recognized that the alignment of all of the laser components is of critical importance in order to maintain maximum output. Especially important is the alignment of the output coupler. U.S. Pat. No. 4,730,335 which is assigned to the assignee of the present invention, describes one means by which laser components are aligned. U.S. Pat. No. 4,890,296, which is also assigned to the assignee of the present invention, describes one means for mounting the output coupler of a laser.
Laser systems also may make use of one or more optical mirrors for bending, splitting, focusing or redirecting beams of light. These mirrors are usually attached to some form of mounting device which is anchored to a supporting surface. It is essential that the mirrors, or other optical components in the path of the laser beam, are in precise and accurate optical alignment with respect to the impinging beam of light. Quite often, after the mounting device is affixed to the supporting surface, some adjustment is necessary.
In the past, adjustments have been achieved by inserting one or more shims between the mount and the supporting surface or base. Some of the disadvantages of this technique are that: it very often involves removing the fasteners which are used to affix the mount to the supporting surface; it is time consuming; that it is not always very accurate; and it is sometimes very difficult to carry out successfully. Small adjustments may be very difficult to make.
Another approach has been to use ball and socket joint mounting devices or double gimbel type mounting devices to hold a mirror on the supporting surface. Although these types of mounting devices enable controlled adjustments to be made, they are relatively expensive and hence not very practical for many applications.
Clearly, there is a need for a simple and relatively inexpensive mounting for an optical component which has an easy to use adjustment capability.